Made of die cast aluminum, Salsbury 4100 series recessed mounted column mailboxes are available in two (2) models. Model #4145 has a 10'' W x 2-1/2'' H solid brass mail flap with the word �MAIL� cast into it and is accessed from the front. Model #4145 includes an 8-1/2'' W x 6-1/2'' H door and a gold finish lock with two (2) keys. A gold finish non-locking thumb latch (#4188) is available as an option upon request. Model #4140 includes an 8-1/2'' W x 8-1/2'' H front door with a gold finish non-locking pull knob. Each model features a durable powder coated finish and is available in four (4) contemporary colors. Each model is also available in two (2) door designs (plain and eagle). Column mailboxes are designed to be recessed mounted in columns, masonry or walls. Column mailboxes may be used for U.S.P.S. residential door mail delivery.